Electric-motor driven pumps



Aug. 16, 1955 s. c. MEREDEW ErAL 2,715,433

ELECTRIC-MOTOR DRIVEN PUMPS Filed Oct. 2, 1951 3 Sheets-Sheet 1 1 )iz rans fwaza Aug. 16, 1955 c, E E E ETAL ELECTRIC-MOTOR DRIVEN PUMPS 3 SheetsSheet 2 Filed Oct. 2, 1951 IN vqura Rs Aug. 16, 1955 G. c. MEREDEW ETAL ELECTRIC-MOTOR DRIVEN PUMPS I5 Sheets-Sheet 3 Filed Oct. 2, 1951 United States Patent Ofifice 2,715,483 Patented Aug. 16, 1955 ELECTRIC-MOTOR DRIVEN PUlVIPS George Charles Meredew and George Clement Stevens,

London, England, assignors to Bernard Bercovitz, Leaside, Ontario, Canada Application October 2, 1951, Serial No. 249,249

Claims priority, application Great Britain February 26, 1951 3 Claims. (Cl. 222181) The invention relates to electric-motor-driven pumps and is concerned with rotary pumps of the kind used principally as fuel pumps in aircraft and in which the motor and the pump, or a major portion of the pump, are constructed or assembled as a unit. it is well known to locate such a unit wholly, or substantially wholly, within a fuel tank of an aircraft with the motor submerged in the fuel and it is known to house the motor in a jacket within the tank and to feed the pump discharge through the jacket thereby to cool the motor and to maintain it submerged in fuel.

According to the present invention a liquid-fuel supply system includes a fuel tank having an opening in one of its side walls, an apertured cover-plate secured to the outside of the tank around the opening, a pump and a motor therefor secured together and both removably supported on the inside of the cover-plate so that whilst the pump normally lies inside the tank and the motor protrudes therefrom through the aperture in the cover-plate they may be removed as a unit through the opening. driving means between the motor and pump, around and spaced from the motor a jacket removably secured to the outside of the cover-plate, a fuel passage from the pump discharge to the space between the motor and the jacket and a fuel outlet from the jacket.

The unit may incorporate a gear drive between the motor and the pump as described and claimed in patent application Serial No. 170,314, now abandoned.

In one construction according to the invention pump has its axis vertical (under normal flight conditions) with the pump inlet at the bottom, the aperture is in a side wall of the tank and the motor axis is horizontal and perpendicular to the cover-plate. With this arrangement the height of the pump inlet in the tank may be varied by adjustment of the position of the cover plate on the tank wall.

One specific construction of a pump unit embodied in an aircraft tank will now be described by way of example and with reference to the accompanying drawings in which:

Figure 1 is a side view of the unit, partly in section,

Figure 2 is a plan view of the unit.

Figure 3 is a section on the line IIIIII in Figure 1, and

Figure 4 is an end view showing the fuel outlets from the motor jacket.

In this example the pump is of the centrifugal type and has an impeller 1 carried on a vertical spindle 2 which is rotated through right-angle gearing 3, 4 by an electric motor 5. The spindle also carries a screw impeller 6 for directing fuel drawn through an inlet gauze 7 into the eye of the impeller 1 and also to assist in separation of vapour and gases in known manner. The output from the impeller is taken from a volute chamber 8 through a passageway 9 formed in the pump casing into the space 10 between the motor 5 and a jacket 11 which surrounds the motor and is provided with alternative connections 12, 13 for attachment of a delivery pipe. A by-pass connection 15 leads directly from the tank into the passageway 9 and is provided with a non-return valve (no shown). The motor is attached to the pump casing by means of screws 16 passing through a flange 17 on the motor and engaging in the pump casing. The jacket 11 is secured to the pump casing by studs 18 and nuts 19.

Clamped between the jacket and the pump casing there is a cover plate 20 which is secured to the side wall 21 of the fuel tank and serves as a closure for an aperture 22 in the wall through which the pump may be inserted into the tank (as shown) or Withdrawn from the tank. The height of the pump within the tank may be varied, to a small extent, by adjustment of the cover plate in the vertical direction.

In use fuel is drawn from the tank through the inlet gauze 7 into the pump impeller and is discharged through the passageway 9, passing through the cover plate into the space It and then out through the particular one of the outlets 12 and 13 which is selected to suit the desired installation. The arrangement ensures that the motor is cooled by the outgoing fuel and is maintained submerged within the fuel. One advantage of the arrangement is that the pump and motor unit is supported at a position adjacent to its centre of gravity so that there is little bending load on the tank Wall.

In an alternative installation the unit is secured with the axes of the pump and of the motor horizontal, i. e. in relation to the arrangement shown in the drawings the unit is rotated about the axis of the motor through and is secured to the cover plate, as before, in that position. With this installation the outlets 12 and 13 extend vertically.

We claim:

1. A liquid-fuel supply system including a fuel tank having an opening in one of its side walls, an apertured cover-plate secured to the outside of the tank around the opening, a pump and a motor therefor secured together and both removably supported on the inside of the cover-plate so that whilst the pump normally lies inside the tank and the motor protrudes therefrom through the aperture in the cover-plate they may be removed as a unit through the opening, driving means between the motor and pump, a jacket removably secured to the outside of the cover-plate and disposed about said motor in spaced relation thereto, a fuel passage from the pump discharge to the space between the motor and the jacket and a fuel outlet from the jacket.

2. A system as claimed in claim 1, wherein the pump has its axis vertical with the pump inlet at the bottom and the motor has its axis horizontal and perpendicular to the cover-plate.

3. A system as claimed in claim 1, wherein the center of gravity of the pump and motor unit lies approximately in the side wall of the tank.

References Cited in the file of this patent UNITED STATES PATENTS 1,960,324 Van Deventer et a1 May 29, 1934 1,960,389 McFerran May 29, 1934 2,292,993 Curtis Aug. 11, 1942 2,361,747 Curtis et a1. Oct. 31, 1944 2,408,918 Curtis Oct. 8, 1946 2,419,146 Kimm et 'al Apr. 15, 1947 

